Tri Z crank seals

[redrider77x]

I am in the process of changing crank bearings and seals on my 86 Z. The new factory seals have large rubber nubs on one side, do the nubs go towards the inside or outside?? I cant remember how they go. The manual shows nubs in but it also says have the markings to the outside and the markings are on the same side as the nubs?? Someone should know... I hope.

[El Camexican]

According to All Balls it dosen't matter. Some guys will tell you markings out.

[oile]

Well I just replaced mine and the nubs were in

[MTS]

Nubs in! They will seal either way...but nubs out on mag side will seal off the oil hole.

[barnett468]

hello,

ok i give in, what are you talking about?

if a crank seal has one spring. the spring side goes in towards the crank.

if it has a spring on each side with no nubs it does not matter.

if it has a spring in each side with nubs sticking off the side of the seal then the nubs go in. if they go out they will prevent the seal from seating all the way.

i'm guessing i'm missing something here, and am afraid to hear what it is, lol.

[El Camexican]

The seals on the Tri-Z (at least the ones from All Balls) are almost, but not quite identical on either side. There are lips and springs on both sides, but they are slightly different. I’m not sure what the term “nubs” is referring to, but it was confusing enough for me that I called All Balls and talk to a tech before putting them in. He assured me that those seals could be installed either way, but if I recall I chose to go letters/numbers out to be safe and because it provided a better surface to push them in with .

Now MTS has me wondering if somehow I didn’t plug off the oil drip hole.

[barnett468]

Hello;

This is drivin me nuts now, lol. I actually looked up the all balls seals before i made my orig post in hopes of seeing the seals up close but the photos were not good enough so i did not see any "nubs".

Also if someone could explain how a "nub" could be so large/huge/big...i guess...that it could block off an oil passage.

If someone had a close up photo it would be interesting to see but if el camexicans bike still runs then i don't see how it matters or that the oil hole is that important.

Also, if the nubs were big enough to block an oil hole i would think that el camexican certainly would have seen them and maybe said "Hey...look at the huge "nubs" on my all balls seals, I wonder what the h__l they are for. They are so big that they might block off my oil hole".

on factory seals, if one side has a "face" that is wider than the other, the wide face always goes out which occasionally leaves you with the very thin, easily damaged face to push it in depending on which way the seal installs.

i'm convinved i'm missing somethin now, lol.

[El Camexican]

One of these days i'll tear mine down, but hopfully someone else has a set they can post up to be stared at now. I know that the two lips were slightly different, but both had springs.

[MTS]

Here are said "nubs" if you put the mag side one in the lack of extra space will let the seal drop in too far and close the drip hole., well i just looked at a main bearing i had laying around, i may have to eat my foot on the drip hole, the nubs acutally slip into the bearing race, so i guess its closed either way.

[El Camexican]

I don't recall the All Balls seals looking like that. Are those OEM?

[barnett468]

Hello MTS;

Thanks for the xlnt photos. Those seals are designed/intended for the "nubs" to go out.

[barnett468]

Hello;


Ok here's part of the deal.

1. The seal in MTS's photo is a GS seal. The factory orig seal is a GS seal.

2. The Yamaha "fish" shows the nubs which face inward on this particular bike. See link below.

http://www.cmsnl.com/yamaha-ytz250n-...6.html#results

3. Both seals have "nubs" on one side.

4. The site I listed shows them in stock. They may still be avail from Yamaha.

5. Since they slip into the bearing race, it is possible that if they were installed with the nubs out, they would have an interference fit with the bearings which could damage the seals. The clearances would need to be measured to determine this.